Bloodstream
by Sleeping Lullaby
Summary: Sam said 'yes' to Lucifer and the end of the world is drawing near. Dean and Castiel might have found a way to stop the devil and save Sam, but in doing so Dean will have to give up the one thing he has left and he's not sure he's willing to do that...


A/N: I came up with this story while I was on the bus listening to Bloodstream by Stateless on repeat and last night I finally wrote it. I hope you like it and that it isn't t too depressing.

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><p>"Do it."<p>

"I can't-"

"You have to, Dean! You have to do it."

Dean took a step back while the angel pressed the familiar silver sword against his chest.

_This couldn't be happening._

"Cas, no…" he said, his voice barely louder than a whisper.

"_Dean_," the angel pleaded and if Dean didn't hear the utter desperation in his voice, one look in the angel's eyes would have told him everything. His once innocent blue eyes were dampened now by his despair. Dean felt sorry for it. More even, he felt _guilty. _The angel had given up everything for him and for what? What had Dean given him in return? Nothing but broken promises, lost faith and death. _"Please."_

Dean had to look away. He could still see the trust in the angel's eyes. The _faith._ Even now, now, after he had failed in every sense of the word and in more ways still, the son of a bitch still believed in him. And it was too much.

He wanted to run. He wanted to jump in his Impala and drive and drive and drive until all he could think of was the soothing noise of the engine running underneath him. Until it was only him and the endless road before him.

But he didn't. He wouldn't. Not now, not ever. Not anymore.

"Cas, I just… can't." Dean knew he sounded weak and pathetic but he couldn't find it in him to care anymore.

"You know it's the only way."

"Well then we'll find another!" he snapped. "Fuck, Cas… I… You have to find something else."

The angel sighed and managed to look impatient. A year ago, _hell_ even a couple of months ago, Dean would have laughed at his expression. Alas, it was not. So he just stared at the other man. Sometimes he felt like staring was all he could do anymore. His face vacant of any emotion except for the moments when he could no longer cope with any of the guilt or pain or anger that terrorized his being.

"There _isn't_ another way. Not if you want to save Sam."

Dean stiffened. His entire body went numb. He pressed his eyes closed and tried to swallow the lump in his throat. A hand came to rest on his shoulder, squeezing gently. And Dean knew that if he were to open his eyes now he would look directly into pretty blue ones filled with a love he didn't deserve.

"Your brother needs you to do this, Dean. _I_ need you to do this."

Dean took a shuddering breath, much to his disgust. "You cannot make me choose between my brother and… and…" And what_?_ He was going to say _my best friend_, but stopped himself the second before the words left his lips. Cas was so much more than just his 'friend'. The things they had been through, the unexplainable amount of trust that ran between them was based on so much more than friendship. Their bond ran that much deeper and was undeniably more profound. Not that he was ever going to mention that to the other guy. End of the world or not, Dean Winchester didn't do chick flick moments. Still, that didn't make it any less true.

"And _you,_" he finished.

When Dean opened his eyes he found the angel much closer to him than he'd expected -the concept of personal space still entirely lost to him. He was smiling that small smile of his and Dean knew the angel had heard everything he hadn't dared say aloud.

Castiel raised his hand to Dean's face and brushed his soft fingers against his cheek. "You don't have to choose, Dean. I'm offering this. I want to do this just as much as you want to save Sam's soul."

Dean doubted that, but didn't say anything instead focusing on the hand that now cupped his cheek and if Dean instinctually leaned into the touch he couldn't be blamed.

"I do. I do want to save his soul. But… Goddammit Cas, I'm not willing to take your life for it!"

"You're not taking it, Dean. I'm giving it. There's a difference."

"Fuck no there isn't! Tell me again why we can't just summon another angel and use their blood instead?"

Castiel sighed and dropped his hand, Dean immediately missed the contact. "Because I'm not going to take the life of one of my brothers who isn't willing to give it for our cause."

Dean looked at the ground. He couldn't do this. He couldn't do this and he told his angel as much.

"I can't do this, Cas. I just can't."

"Dammit, Dean! This isn't just about _you_! Millions of people are dying. The world is being turned into ash as we speak. Lucifer needs to be stopped and this is the way to do it!"

Dean knew Castiel was right. It was the only way. Months and months of research had already proven that. But all he could think of was that he couldn't lose Cas too. He suddenly realized that he needed the angel more than he was prepared to admit to himself. Dean couldn't possibly murder his best friend. Even if doing so would be his brother's salvation. He couldn't slit the man's throat, gather his blood and use it in a spell to weaken Lucifer enough to allow Sam's soul to move on and enable him to lock the bastard back into his cage. He couldn't- _No!_ Just no.

But this wasn't just about his brother's soul, was it? There was so much more at stake here. So many lives that depended on what he decided to do here.

"You can't ask me to do this, Cas."

"I'm not asking. I'm simply stating what you need to do."

"I can't take your life."

"I _want_ to do this, Dean," and he spoke with such conviction Dean couldn't possibly doubt his willingness. "I'm willing to give my life for our cause. If you recall, I've done so several times already." He smiled gently. "If my death would mean that you'd come even a fraction closer to defeating the devil then it's more than worth it. I don't see this as a sacrifice, Dean."

And that's what bothered him. The angel so readily gave his life like it was nothing, for a cause Dean didn't even seem to believe in anymore. The angel said all of this like he didn't think it was possible for Dean to fail this impossible task. But Dean knew, Dean _feared_, that it would be all for nothing. That he would end up killing this angel and then screw everything up. Then the angel's sacrifice would have been for nothing and he would be left here without a brother, without his friend, without family. All alone.

Castiel seemed to guess his train of thoughts because suddenly two strong hands cupped his face and he was forced to look into beautiful and still very vivid eyes.

"You listen to me, Dean Winchester. You will not fail. Do you understand? I wasn't ordered to go all the way to hell and back again to safe some powerless and weak and utterly insignificant soul. No, I was sent to safe _you_. You have a strength, Dean, that is unparalleled. Your soul shines brighter than any I've ever seen. Even in the darkest of places surrounded by shadows that should have broken you beyond repair and sucked the light out of you leaving nothing but darkness and cruelty instead, you still shone. They couldn't dim your light, your will to survive. You're much stronger than you realize, Dean. I know you. I pulled you out of hell and rebuilt you with my own hands. My grace has touched your soul. So believe me when I say that I know beyond any doubt that you will not fail. God didn't create such a soul for no reason. You're meant to do this, Dean. You're meant to save the world." Castiel reached up and kissed his forehead. He then picked up the angel sword from where it had fallen on the ground and wrapped Dean's hands around it. "So let me help. Let me help, Dean. In any way that I can. Because this is your fight, but I will not let you fight it on your own while there's still something I can do to simplify your path."

Dean didn't know what to say to that. He couldn't find the right words. And even if he could he doubted that they'd be able to express what he wanted to tell the angel. So he did the only thing he could come up with. The only way in which he knew how to express himself.

He leaned forward and kissed him. Castiel gasped in surprise, but didn't hesitate to return the kiss. Dean didn't know what he was doing or why or what it meant. He only knew that he needed the angel. Needed him more than he could tell. But at the same time he knew Castiel was right. He knew this was something he had to do. Not because it was God's plan or because it was his destiny but because of the millions of people out there who hadn't done anything wrong and were helpless against the wrath of a fallen angel. But Dean had the power to save them. To put an end to the apocalypse. If only because _his_ fallen angel believed in him.

He kissed him passionately. Hungrily. As if he'd been drowning and Cas' lips were the much needed air and the angel returned all of it with an equal craving. One arm wrapped around the angel's back while the hand of the other grasped fistfuls of thick black hair, Dean wondered why they had never done this before. It just felt so _right._

He didn't want it to end. He wanted it to go on and on and on until they'd forgotten which limps were theirs and which were the other's. Until they'd fucked each other brainless. He pressed a little closer to Cas when he realized the 'until' would never come. He knew what he had to do when they'd pull away and he knew that moment would come too soon.

After several long minutes of intense kissing and languid strokes of tongue they pulled away. Both of them unwilling. Both wishing they'd had a moment longer.

Castiel brought his hands up to his tie and loosed the knot, unable to tear his eyes away from Dean's. There was so much there. In his eyes. So many feelings. So many things Dean would never know. An image that would haunt him for the rest of his life he supposed. The angel took off his tie and dropped it on the ground, undoing the first buttons of his shirt and exposing his neck.

For a moment, they just stood there. Staring at one another. Unspoken words and untouched feelings hanging heavily between them. Dean raised his hand and stroked the soft white skin of Cas' neck. A whimper escaped his mouth when their skins touched and suddenly he was on Cas again. Kissing whichever part he could reach. His mouth attaching to Cas' neck, gently sucking the unveiled skin.

The throaty sounds that left Cas' lips made Dean shudder and he memorized it all. The way he felt against his body, the way he smelled, sounded, looked –all wide-eyed and fuckable- and simply the way he was.

Only when he noticed his angel shuddering heavily did he pull back a little. When their eyes met Dean's heart clenched painfully. He used his hands to wipe Cas' tears away and the angel smiled sadly and raised his hands to return the favor. _Had he been crying?_ Only then did he notice that it wasn't Castiel that was shuddering but himself. He closed his eyes for a second, trying to stop the tears from falling and failing miserably.

He took a shaky breath and smiled at Castiel, leaning in for another kiss. Another stolen moment.

"_Cas_," he whispered brokenly against the other man's lips. "I…"

_Love you._

"I know," Castiel whispered back after which he pressed their lips together again. "I know." His voice broke.

Without thinking Dean gathered the angel in his arms and held him as close as he could. One hand brushing soothingly through his hair as his lips skimmed over the addictive skin of his neck and the hidden spot behind his ear.

"I love you too," Castiel murmured softly and Dean had to silence a sob by pressing his face into the crook of Cas' neck.

_This couldn't be happening._

"I know," he sobbed. "I know."

And he slit the angel's throat.


End file.
